Brief Answer:
I would like to know the test which you went through at 51 days..

Detailed Answer:
Hello. Welcome back.

In my last interaction with you I had asked you to clarify whether the 51 day test was purely an antibody based test Or a Combo i.e antigen/antibody based test?? Kindly refer back to the discussion...

http://doctor.healthcaremagic.com/AskDoctorInboxServlet?page=viewQuery&queryId=182788

If your 51 day test was a Duo/ Combo (i.e tested both for HIV antigen as well as antibody against HIV) then it is conclusive..
However if your 51 day test was purely an antibody based test (RAPID/ SPOT TEST) then only a 12 weeks test would be conclusive.

Most of the healthy individuals who get infected with Hiv have detectable antibodies against Hiv at 4 weeks therefore even a negative antibody based test at 4 weeks is fairly indicative but it is not conclusive at 4 weeks, because few individuals who may not yet have detectable circulating antibodies at 4 weeks.

A repeat screening test at 12 weeks is to cover for this window period of Hiv detection in those few individuals (those who are Hiv infected but not yet have detectable circulating antibodies at 4 weeks).
Most of these few individuals will subsequently develop detectable circulating antibodies by 12 weeks. Therefore 12 weeks testing is taken as final/ conclusive for an ANTIBODY BASED TEST.

On the other hand, HIV DUO/ HIV COMBO test reduces the window period to 4 weeks.
Combo test detects both circulating Hiv antigens (P 24) as well as antibodies against Hiv and has a better predictive value at 4 weeks and beyond as compared to a purely antibody based test.
P 24 antigens appear as early as 2-4 weeks & therefore would also be detected by Combo test, in those very few in whom antibodies have not yet appeared... these individuals would normally be missed by a purely antibody based test.

So kindly let me know the test which you went through at 51 days...

Regards

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